With the development of liquid crystal display technology, the current consumer has higher and higher requirement on product resolution. Products with high resolution have gradually become the mainstream in the market. High resolution means that the charging time for each row of pixels in an equipment must be shortened, and the on-state current of corresponding switching element (e.g., thin film transistor (TFT)) must increase, so as to charge and discharge a pixel electrode in a shorter period of time. In the aspect of the structural design of an array substrate, the mostly direct method of increasing the on-state current of the switching element is to increase the width-to-length (W/L) ratio of the switching element. For instance, higher W/L ratio may be obtained by increasing the size of a single switching element or using a plurality of switching elements in parallel connection. However, in the case of increasing the W/L by these means, an area used for displaying in each pixel region is occupied, so the aperture ratio of the pixel region may be reduced.